In the related art, an image forming apparatus has been known which includes a photosensitive member cartridge having a photosensitive member, a waste developer container configured to accommodate therein developer collected from the photosensitive member, and an exposing unit arranged in front of the photosensitive member cartridge and configured to expose the photosensitive member (see, for example, JP-A-2005-070261). In this image forming apparatus, the photosensitive member cartridge is configured to be mounted and demounted from above an apparatus main body, and the waste developer container is configured integrally with the photosensitive member cartridge and is arranged above the photosensitive member.
Regarding a configuration where the photosensitive member cartridge is to be mounted and demounted through below the exposing unit, according to the configuration disclosed in JP-A-2005-070261, since the waste developer container is arranged above the photosensitive member, the waste developer container may interfere with the exposing unit when mounting and demounting the photosensitive member cartridge.
In the related art, another type of image forming apparatus has been known in which a front cover is provided with an urging member so as to press a developing roller to a photosensitive drum and the urging member pushes a developing cartridge to press the developing roller to the photosensitive drum when the front cover is closed (see, for example, JP-A-2006-106020).
However, in this image forming apparatus, since the front cover is applied with a reactive force of the urging member, it is necessary to increase the stiffness of the front cover. Also, the front cover is difficult to be closed and is likely to be unnecessarily opened.
Also, if the urging member is provided for a replacement component such as the developing cartridge, it may be necessary to provide the urging member for each replacement component, so that the cost of the replacement component increases.